**Exhibit 10.11**

[BIOTRANSPLANT LOGO]

Building96, 13thAvenueCharlestown Navy YardCharlestown, MA 02129Tel. 617/241-5200Fax: 617/241-8780

June 29, 1992

James A. Hope, Ph.D.146 Prospect StreetHingham, MA

Dear James:

This will confirm our offer to you tojoin BioTransplant, Inc. on the following terms:
| 1.     | Title:           | Vice  President of Development of BioTransplant, Inc. reporting to the President.                                                                                                                                                                                                                                                                                                                                                                                                    |
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| 2.     | Terms  of Offer: | This  offer is contingent on your starting employment on or by August 3, 1992.                                                                                                                                                                                                                                                                                                                                                                                                       |
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| 3.     | Compensation:    | $125,000  per year.  Bonus eligible.  $5,000 to be paid as a salary advance on  the first day of employment.  Base  salary for the first 12 months of employment remains at $125,000.                                                                                                                                                                                                                                                                                 |
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| 4.     | Benefits:        | Standard  package, as provided by the company including life insurance at 1x salary,  medical and dental insurance (85% of premium paid by company, 15% balance  paid by employee), disability insurance, paid parking at the Charlestown Navy  Yard, three (3) weeks paid vacation/personal time accrued on an annual basis,  and 10 paid holidays per year.  The  company will provide funds to cover COBRA benefits on existing health  insurance until BTI coverage begins. |
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| 5.     | Equity:          | Option  to purchase 100,000 shares of common stock granted at Fair Market Value,  vested in equal installments over four (4) years beginning with the first  anniversary of employment as determined by the Board.  Stock is subject to repurchase at cost and  restriction on sale if terminated for cause.   Eligible for future stock options at the end of each year subject to  the discretion of the Board.                                                          |
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| 6.     | Severance:       | In  the event your employment is terminated by BioTransplant without cause, you  would receive up to 6 months base salary, payable in 6 equal installment  which would be discontinued upon your securing other employment.  If employment has not been secured after 6  months, an additional severance payment of up to 6 months base salary would  be negotiated.                                                                                                            |
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| 7.     | Agreements:      | Your  employment is subject to your signing a Confidentiality, Invention Assignment  and Non-Compete Agreement with BioTransplant and review of any agreements you  may have with others to insure that your employment by BioTransplant is not  in conflict with any such agreements.                                                                                                                                                                                               |

If these terms are acceptable, pleasesign and return one copy of this agreement.

We are very enthusiastic about yourjoining the company.

With best regards.

Sincerely,

/s/ Elliot LebowitzElliot Lebowitz, Ph.D.President and Chief Executive Officer

AGREED TO
| By:    | /s/  James A. Hope    |   | Date:  | 7/6/92 |
|--------|-----------------------|--------|--------|--------|
|   |                       |   |   |        |
|   | James  A. Hope, Ph.D. |   |   |   |